For some time now one of the most practical and efficient nutcrackers has been the so called "Inertia" nutcracker of the type shown in U.S. Pat. No. 3,524,486. This nutcracker has been commercially successful and is generally referred to as an impact type inasmuch as the same is adapted to hold a nut between an impact member and an anvil. A striking member is designed to be cocked and released after which the same drives towards the impact member and strikes the same. This striking force results in a compressive movement between the anvil and impact member, resulting in the nut being cracked.
In an impact nutcracker of the type shown in U.S. Pat. No. 3,524,486, both the anvil and opposed impact member include conically shaped nut receiving recesses. This is important since the design is aimed at providing opposed points of contact about opposite extremities of the nut. This is a very suitable design for relatively soft-shell nuts as pecans, English walnuts or the like. But because the nut receiving recesses are conical shaped, this results in only point or minimum contact of the nut with the recess portions of the impact member and anvil. Point or minimum contact is very effective in cracking nuts such as pecans and English walnuts. But in the case of hard-shell nuts such as black walnuts or macadamia nuts, point or minimal contact is not effective in cracking such nuts with a single blow. At best point contact results in small cracks at the point of contact and consequently some individuals choose to turn the hard-shell nut numerous times resulting in a plurality of small cracks, and continuing this until the shell is sufficiently cracked to remove the kernel. Even in such situations, the kernel may be battered into a great many small pieces, which further hinders the efficiency of the nutcracking operation.
In view of this, there has existed and continues to exist a real need for an impact nutcracker that is capable of cracking hard to crack nuts such as black walnuts and macadamia nuts in the same way that the conventional impact nutcracker has been able to crack pecans and English walnuts.